/Engine/Plugins/Animation/RigLogic/Source/RigLogicLib/Public/pma/resources/ArenaMemoryResource.h
Regions = {initialSize, regionSize, regions[1] * growthFactor, regions[2] * growthFactor, ... , regions[n - 1] * growthFactor}
ArenaMemoryResource ( std::size_t initialSize, std::size_t regionSize, float growthFactor, [MemoryResource](API\Plugins\RigLogicLib\pma\MemoryResource) * upstream )